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.\"     @(#)umount.8	8.2 (Berkeley) 5/8/95
.\"
.Dd May 8, 1995
.Dt UMOUNT 8
.Os BSD 4
.Sh NAME
.Nm umount
.Nd unmount filesystems
.Sh SYNOPSIS
.Nm umount
.Op Fl fv
.Ar special | node
.Nm umount
.Fl a | A
.Op Fl fv
.Op Fl h Ar host
.Op Fl t Ar type
.Sh DESCRIPTION
The
.Nm umount
command
calls the
.Xr unmount 2
system call to remove a
.Ar "special device"
or the remote node (rhost:path) from the filesystem tree at the point
.Ar node .
If either
.Ar special
or
.Ar node
are not provided, the appropriate information is taken from the
list of filesystems provided by
.Xr getfsent 3 .
.Pp
The options are as follows:
.Bl -tag -width indent
.It Fl a
All the filesystems described via
.Xr getfsent 3
are unmounted.
.It Fl A
All the currently mounted filesystems except
the root are unmounted.
.It Fl f
The filesystem is forcibly unmounted.
Active special devices continue to work,
but all other files return errors if further accesses are attempted.
The root filesystem cannot be forcibly unmounted.
.It Fl h Ar host
Only filesystems mounted from the specified host will be
unmounted.
This option implies the
.Fl A
option and, unless otherwise specified with the
.Fl t
option, will only unmount NFS filesystems.
.It Fl t Ar type
Is used to indicate the actions should only be taken on
filesystems of the specified type.
More than one type may be specified in a comma separated list.
The list of filesystem types can be prefixed with
.Dq no
to specify the filesystem types for which action should
.Em not
be taken.
For example, the
.Nm umount
command:
.Bd -literal -offset indent
umount -A -t nfs,hfs
.Ed
.Pp
umounts all currently-mounted filesystems of the type
.Tn NFS
and
.Tn HFS .
(The
.Fl a
option only unmounts entries in the
.Pa /etc/fstab
list.)
.It Fl v
Verbose, additional information is printed out as each filesystem
is unmounted.
.El
.Sh NOTES
Due to the complex and interwoven nature of Mac OS X,
.Nm umount
may fail often.  It is recommended that
.Xr diskutil 1
(as in, ``diskutil unmount /mnt'') be used instead.
.Sh SEE ALSO
.Xr unmount 2 ,
.Xr getfsent 3 ,
.Xr mount 8 ,
.Xr diskutil 1
.Sh HISTORY
A
.Nm umount
command appeared in
.At v6 .
